The length of second pendulums is 1 m on earth . If mass and diameter of the planet is doubled than that or earth length becomes :

The length of second pendulums is 1 m on earth . If mass and diameter

1.	The length of second pendulums is 1 m on earth . If mass and diameter of the planet is doubled than that or earth length becomes :
Answer» 2 m `0.5 m` 4 m 1 m Solution :Time PERIOD of a second pendulum is 2S. When second pendulum is on earth then `T= 2pi sqrt((l)/(g))` (or) `2= 2pi sqrt((R^(2)l)/(GM)) ""....(1)` When second pendulum is on the planet then `=2pi sqrt(((2R)^(2)xxl')/(G(2M)))` `=2pi sqrt((2R^(2) l')/(GM)) ""...(2)` From (1) and (2) we get `sqrt(2l')= sqrt(l)` (or) `l'=(1)/(2)=(1)/(2)=0.5 m`.